Google is moving to materialize all of its apps and now the well known Google Keyboard is getting a touch of Material Design.
Google Keyboard version 4.0.2 will be directly rolling out to users, and the biggest change in this new version is the new two classy Material themes: Dark and Light with the original existence of the Holo White and Holo Blue theme. Ultimately, users prefer a logical look on Google Keyboard since Google is updating all of its apps to Material Design.
And in order to apply the new themes, users can go to Setting>Language and Input.
Although this is not much of an update besides the Material Design and the two new themes, hopefully in the future Google Keyboard might add some extra features in its system.
Source: Android Authority